Features: The filters kit includes 8 different colors, 8 pieces in total. Comes with ge-neral standard inch thread (Fine Thread), suitable for most telescopes. Easy to install and use, a great choice for astronomical telescope lovers. Made of high quality aluminum alloy and optical glass, this product is sturdy and durable. It can reduce eye strain and improve contrast and surface detail of the planet. Fitting for enhanced views of the Moon, Jupiter, for Mars, for Saturn, star cluster, nebula, deep for sky, etc.Black filter is used as a solar filter. Don'for t use it when the for sun is particularly strong. Black filter: solar filter, it is strongly required to use this solar filter in the morning and evening. Do not use it especially when the sunlight is very strong (noon)! Specifications: Material: Aluminum Alloy+Optical Glass Diameter: 4cm/1.57 in Barrel size: 1.25 " /31.7mm Package Includes: 8 Pieces Color Filters note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item.